BACKGROUND The use of transcranial Direct Currant Stimulation (tDCS) to study anatomical and physiological dynamics and circuits supporting cognition and executive functions in particular has dramatically increased in recent years. However, its mechanisms of action remain only partially understood. OBJECTIVE In this study we assess the cognitive and physiological effects of anodal tDCS to the DLPFC on executive function in order to understand (1) the role of DLPFC laterality, (2) the physiological dynamics sustaining the modulation of executive function by tDCS, and (3) the impact of state-dependent dynamics. METHODS In a randomized, placebo-controlled, cross-over study, we applied anodal tDCS targeting the left vs. right DLPFC vs. sham in 20 healthy individuals (10 males, 10 females). Immediately before and after tDCS, subjects performed the Flanker Task while we measured behavioral (reaction time and accuracy) and neurophysiological (ERP) responses. Specifically, the amplitude of N200, P300, ERN and Pe is compared before and after stimulation. RESULTS Anodal tDCS to the left DLPFC lead to a significant improvement in reaction time, an increase in P300 amplitude and a decrease in N200 amplitude in a state-dependent manner: baseline ERP amplitudes conditioned the effects of tDCS. CONCLUSION Given the role of these ERPs in conflict-related tasks, we speculate that tDCS is modulating the subconstructs of selective attention, conflict monitoring and response inhibition. These findings contribute to a further understanding of the role of left DLPFC in the modulation of executive function, and shed light into the mechanisms of action and the state dependent nature of tDCS.

中文翻译：

---

左侧 DLPFC 的 tDCS 以状态依赖的方式调节执行功能的认知和生理相关性

背景技术 近年来，使用经颅直接电流刺激（tDCS）来研究解剖学和生理学动力学以及支持认知和执行功能的回路尤其显着增加。然而，其作用机制仍然只有部分被了解。目的 在本研究中，我们评估阳极 tDCS 对 DLPFC 对执行功能的认知和生理影响，以便了解 (1) DLPFC 偏侧性的作用，(2) tDCS 维持执行功能调节的生理动力学，以及（ 3）状态相关动态的影响。方法 在一项随机、安慰剂对照、交叉研究中，我们对 20 名健康个体（10 名男性，10 名女性）应用了针对左侧 DLPFC 和假手术的阳极 tDCS。在 tDCS 之前和之后，受试者立即执行侧翼任务，同时我们测量行为（反应时间和准确性）和神经生理学 (ERP) 反应。具体地，比较刺激前后N200、P300、ERN和Pe的幅度。结果左侧 DLPFC 的阳极 tDCS 导致反应时间显着改善，P300 振幅增加，N200 振幅以状态依赖性方式减少：基线 ERP 振幅调节 tDCS 的效果。结论 鉴于这些 ERP 在冲突相关任务中的作用，我们推测 tDCS 正在调节选择性注意、冲突监控和反应抑制的子结构。这些发现有助于进一步了解左 DLPFC 在执行功能调节中的作用，并揭示 tDCS 的作用机制和状态依赖性。